Elevated expression of nuclear protein kinase CK2α as a poor prognosis indicator in lymph node cancerous metastases of human thyroid cancers.

AIM To investigate the expression of protein kinase CK2α (CK2α) in human thyroid disease and its relationship with thyroid cancer metastasis. MATERIALS AND METHODS Using immunohistochemistry we measured the expression of CK2α in 76 benign and malignant human thyroid cancer tissues, including 10 pairs of papillary carcinoma tissues with or without lymph node cancerous metastasis and similarly 10 pairs of lymph nodes. RESULTS The expression of CK2α was found to be higher in thyroid carcinoma cases (papillary carcinoma, follicular carcinoma, anaplastic carcinoma and medullary carcinoma) than in ones such as chronic lymphocytic thyroiditis, nodular goiter and adenoma. These findings were also confirmed by RT-PCR and Western blotting. More strikingly, elevated expression of CK2α in thyroid papillary carcinoma tissues was not only significantly associated with lymph node cancerous metastasis and clinical stage of thyroid cancers; but also correlated with epithelial-mesenchymal transition (EMT) and high tenascin C (TNC) expression. In addition, EMT and high TNC expression in thyroid carcinoma tissues was significantly associated with lymph node cancerous metastasis. CONCLUSIONS Elevated expression of nuclear CK2α is a poor prognosis indicator in lymph node cancerous metastasis of human thyroid cancers.